The present invention relates to a safety syringe, particularly a simple syringe structure which can have its needle cannula retracted into its hollow plunger after injection to assure the safety of medical personnel and prevent reuse of the used syringe.
A conventional disposable syringe is made of plastic material and without indicating means to show whether it is brand new or used. A used syringe may be reused due to negligence or for lowering of operating costs, and consequently the patient who receives an injection with a used syringe may be infected by AIDS, hepatitis or other diseases transmitted through body fluid contact. Moreover, medical personnel who disposes of used syringes may be injured by a used needle cannula or infected with diseases from contact with the used needle cannula.